Empire Earth Anti Cheat

Hello all guys

I had tried Editting Exe File which was made by C++
I am making A patch to stop cheating through Tribution screen
I am trying to stop Right Mouse Click on combobox through hex editor or assembly..but could not even find the exact comboboxes which are responsible to tribute buttons...>>>I tried so many times
look to attachement
If u click Left mouse button to set the amount of money to send ..the combobox value will increasse by 100 of each click but if u click shift+Left Mouse button,Combobox value will increase by 500 >>but if u press right mouse click it will decrease by 100 and with shift.decreasing by 500..so i want to disable right mouse button in this menu only>>but dont know how to do it...Also as u saw in that picture there is a number above the combobox ..that number decreasing while the combobox amount increasing..and if the combobox decreasing means the above of combobox number is increasing...
If you can help fot free answer me here,If u want me to pay just contact me
Plz Help